Draftsman s instrument



struetion which I now shallproc'eed to describe v with reference to the accompanying drawings,

=fined in the claims at the close of this speci- NITED STATES oSoARfF. HILL, on LowELL, MASSACHUSETTS.

o RAFTSMANS lN ST-RU M ENT.

SPECIFICATION forming part of Letters Patent N 0. 531,186, dated December 18, 1894.

Application filed October 28, 1893 To all whom it may concern: 7

Be it known'that I, OSCAR F. HILL, a citizen ofthe United States, residing at Lowell, in the county of Middlesex and State of Massachu setts, have invented. certain new and useful Improvements in Draftsmens Instruments, of which the following is a specification, reference being had therein to the accompanying drawings. v v

The objects of my invention are to provide an improveddraftsmans instrument fitted for use in all the ways in which the ordinary triangle is fitted for being used and specially designed for being employed in making parallel lines for surface and section shading, of more compact and convenient arrangement and construction than like instruments which have been devised heretofore, and having the various parts thereof combined and connected in novel manner.

The various instruments of thesame general character which have been devised heretofore have presented different objections and disadvantages which are obviated by my invention. The greater number thereof are complicated in construction, and costly. Others have the defect of being made in two or more disconnected parts which have to be held together by hand while being used, and hence are more or less inconvenient to' use, the said parts being likely to become separated and misplaced when not in use. Still others have the parts thereof so disposed and connected as to restrict the use of the triangles forming portions of the same.

The invention consists in the draftsmans instrument of improved character and conafter which the novel features thereof will be particularly pointed out and distinctly defication.

In the drawings, Figure 1 is a view in plan illustrating a draftsmans instrument embodying the preferred form of my invention. Figs. 2 and 3 are views of certain portions of the instrument which is represented in Fig, 1, showing the same parts in difierent positions.

At 1 is shown a triangle, which may be of Serial No. 489.375. As model.)

at 2 an opening made centrally through the body thereof, as usual.

' 3 is a supplemental piece preferably located within the said opening 2, and united to the which are pivotally connected at their ends with the supplemental piece 3 and base 11 by means of the four screws marked 5, 5, 5, 5.

At 6 is shown a gage which is pivoted to the thereof to the other, and into the said opening enters a pin or other projection 8 on the supplemental piece 3. The base 11 of the triangle and the supplemental piece 3 are formed with holes 9, 9 of size sufficient to receive the tips of ones fingers, such holes, if desired, being made ontirely through the said parts to permit the finger-tips to contact with the paper on which the instrument rests, and form frictional cushions for engagement therewith. 7

The manner of using my instrument will be obvious. The triangle having been laid upon the paper which is being drawn upon, the base of the triangle is applied in customary manner to the edge of the blade of a T-square, and the tips of two of the fingers of one hand of the draftsman are placed in the openings 9, 9.

down upon the base of the triangle to holdit more firmly against the paper. The triangle being thereby held stationary, a slight advance of the other finger then serves to move the supplemental piece forward until the pin or projection thereon brings up against the forward side of the opening in the gage. The supplemental piece is then in its turn borne .down by its finger to hold it fixedly against the paper, and the pressure upon the triangle being slightly relaxed, the corresponding finger is moved to shift the triangle forward until the rear side of the opening in the gage brings up against the pin or projection on the supplemental piece. This having been accomplished, the triangle is in position for the ruling of the next line, and so on. By mov ing the gage on its pivot in one direction or' the other, the extent of play of the pin or proany ordinarycharaeter and construction, and

jection within the opening of ,the gage, and

side 12 of the triangle by a screw 7, the said gage beingformed with an opening or slot 61 therein which graduallywidens from one end base 11 of the triangle by parallel links 4, 4, 7

After each line is ruled, one finger is borne V correspondingly the extent of the movement of the triangle and supplemental piece relatively to each other, and the width of the spaces between the ruled lines, may be varied. Fig. 1 shows the gage in an intermediate position, and Fig. 3 shows it in the position in which the widest portion of its opening is presented to the pin or projection on the supplemental piece. Fig. 2 shows the gage moved into the extreme position which is opposite to the position represented in Fig. 3, and with the gage having a slot made of the proportions shown this position of the gage will cause the pin or projection to be held so that it cannot play or move laterally. The gage may be shifted into any of the positions which are intermediate those represented in Figs. 2 and 3.

As will be apparent, the preferred arrangement of the parts is such that exteriorly the instrument is exactly the same as an ordinary triangle, and it may be used for all the purposes for which the latter is used, and in precisely the same manner. Various changes may be made in the means and manner of connecting the parts together, without depart H ing from the spirit of my invention.

I claim as my invention- 1. The draftsmans instrument consisting of the triangle, the supplemental piece movably attached to the triangle and located within the central opening of the latter, and the adjustable gage for limiting the movement of the said parts relatively to each other and graduating the extent of such movement, substantially as described.

2. The draftsmans instrument consisting of the triangle, the supplemental piece mov-' ably attached to the triangle and located within the central opening of the latter, and the adjustable gage having the opening of varying width for limiting the movement of the said parts relatively to each other and graduating the extent of such movement, substantially as described.

3. The draftsmans instrument consisting of the triangle, the supplemental piece located within the central openingof the triangle, the parallel links connecting the said parts, and the pivoted gage having the opening of varying width for limiting the movement of the triangle and supplemental piece relatively to each other and graduating the extent of such movement, substantially as described.

In testimony whereof I aifix my signature in presence of two witnesses.

OSCAR F. HILTi.

Witnesses:

JAMES F. SAVAGE, M. LOUISE VARNUM. 

